Protein and Your Horse - A Horse of Course Monthly Horse Column

If the average performance horse needs about 10 per cent protein, just throw him a four-foot long 2 X 4.

One nutritional study done on a piece of wood had the wood testing at 12% crude protein.

Purina Mills tested a concoction of wood chips, clay, 10W40 motor oil and lawn fertilizer and it tested at 14% crude protein.

Can a horse digest either study protein source? Nope!

Are some of the ingredients in horse feeds edible, yet the protein cannot by utilized? Yes, says Eleanor Richards, a nutrition specialist.

So what is the point of the studies and what can we learn?

Learn to read a feed-bag tag, learn how much protein your horse needs and learn to balance feed protein and forage protein to get the correct amount of protein for your horse.

Richards says horses need protein for development and repair of muscle, healthy skin, hair, and hooves, for milk production, reproduction and the maintenance of healthy red blood cells and bone. Notice, she says, the list does not include weight gain or energy.

Here are minimum daily crude protein requirements: mature idle horses 8.5%, mares in last 90 days of pregnancy 11%, mares in lactation 14%, foals 18%, weanlings 16%, yearlings 13.5%, two-year-olds 10% and performance horses 10%.

The first nutrient listed on a feed-bag tag is crude protein. To get an idea if the protein is highly digestible, look at the feed-bag tag to see what makes up the feed. The best source of protein is soybean meal that is rich in lysine and other amino acids, meaning digestibility is high. But soybean meal is expensive, so lower quality feeds will use corn gluten meal, linseed meal, brewer’s grain and distiller’s grain.

“You get what you pay for, and cheap feeds usually aren’t cheap,” says Richards.

So by looking at the feed-bag tag you can get a good idea about the digestibility of the protein---and most of the time it is much better than a 2 X 4 chunk of wood.

Now determine if you horse is getting his or her daily requirement of protein.

If your horse is eating 5 pounds of 10% crude protein grain and 15 pounds of grass hay that has tested at 6% crude protein, you need to do some math. Five pounds of grain times 10% equals 50; 15 pounds of hay times 6% equals 90. Add those together and you get 140 units of protein per day. Now add the total weight of the feed per day, 5 pounds and 15 pounds and you get 20 pounds per day. Divide the feed weight into the protein units (20 divided into 140) and you get 7% protein in the horse’s diet.

That’s not good enough if your horse needs 10% protein per day.

“You’ll have to make the adjustments by feeding a higher protein forage or a higher protein grain,” says Richards. “In most cases I would suggest a higher crude protein forage.”

There is no benefit to feeding more protein than your horse requires, Richards says. And she points out that in addition to wasting money, feeding excessive protein can cause health problems.

Some protein is stored and used as energy, but most excessive protein will be excreted as waste.

Horses tend to purge their systems of excessive amounts of protein by drinking large amounts of water, which can result in kidney problems and very wet stalls.

When it comes to protein, Richards says: know your horse’s requirement, offer plenty of good quality forage, know the protein level of the forage, buy a good quality prepared feed and feed according to the directions.